Official US Government Icon

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure Site Icon

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

 Find the latest Coronavirus-related transportation statistics on the BTS COVID-19 landing page.

United States Department of Transportation United States Department of Transportation

Estimated U.S. Emissions of Nitrogen Oxides

(Million short tons)

Dataset Table:

Year TOTAL Highway vehicles Off-Highway Fuel combustion 1
1970 26.88 12.62 2.65 10.06 2
1975 26.38 12.06 2.97 10.49 3
1980 27.08 11.49 3.35 11.32 4
1985 25.76 10.93 3.58 10.05 5

Embedded Dataset Excel:

Dataset Excel:



Details may not add up to totals due to rounding in the source.


KEY: R = revised.

aIndustrial processes consists of chemical and allied product manufacturing, metals processing, petroleum and related industries, and other industrial processes; and solvent utilization, storage, and transport.


U.S. Environmental Protection Agency, Air Emissions Inventories, Air Pollutant Emissions Trends Data, National Annual Emissions, available at as of May 7, 2020.